My understanding from speaking to the AUK chair (& ACP rep) over breakfast at the AGM is that ACP have tentatively agreed to accept our overall climbing amount for the purposes of the R10000 award, hence BCMs likely inclusion.
As AAA assessments (in Great Britain at least) use a more accurate data source based off OS physical terrain measurements, as opposed to the generally available satellite-sensed elevation models used globally, it's tricky to reconcile this into a single, global algorithm, not least because seemingly every routing service (RwGPS, Komoot, Strava, OpenRunner, Garmin) all produce differing results from the same sources. There's probably a PhD's worth of research to be done here if anyone is looking for GIS doctorate ideas.